Late last week the vessel set down the final pipe next to the riser platform. The 36-in. line, which stretches 283 km (176 mi) from the field to the Mongstad oil terminal outside Bergen, is said to be Norway’s longest and largest to date, in water depths of up to 537 m (1,762 ft).
“It has been a significant operation involving more than 600 people…who have welded together over 23,000 pipes,” said Geir Bjaanes, responsible for subsea, power and pipelines for the Johan Sverdrup project.
At peak, 660,000 b/d of oil will flow to the terminal.
TheCastorone started pipelay operations at Mongstad in late April. After installing the approach section through the Fensfjord, the vessel then set course for the Johan Sverdrup field.
Next up for theCastorone is the 156-km (97-mi) long, 18-in. gas pipeline that will extend from the Johan Sverdrup field center to the Statpipe pipeline, for onward shipment to Kårstø. Laying should be completed during the fall.
On completion, the 2018 Johan Sverdrup installation campaign will have finished, comprising three jackets, two topsides, one bridge, more than 400 km (248 mi) of pipelines, and 200 km (124 mi) of power cables.
Next year the last two Phase 1 topsides and remaining bridges will be put in place before first oil in November.